1. Field of the Invention
The present invention relates to a mini anchor for installing a seatbelt device. More particularly, the structure of mini anchor is provided a proper clearance for directly mounting on a vehicle body instead of applying a busing used in a conventional assembly.
2. Description of the Related Art
Generally, a seatbelt is rolled up when it is not in use by the user, and it is unrolled from the rolled-up state when the user pulls the seatbelt to wear it.
FIG. 1 illustrates a typical seatbelt being mounted on an automobile seat. One end of connection belt (20) is mounted on one side of passenger seat (D) by an anchor (70). A buckle (10) is attached at the other end of connection belt (20). A retractor (30) is fixed at the lower part of passenger seat (D) or vehicle body (B). A pillar anchor (60) is fixed at the upper part of vehicle body (B) locating just above passenger""s shoulder for suspending the seatbelt. The seatbelt (40) is rolled up and stored inside the retractor (30) as a reservoir. A coupler (50) is attached at the end of seatbelt (40) for coupling or uncoupling the buckle (10) depending on the passenger""s intention. The seatbelt (40) is suspended through the pillar anchor (60) for easily operating by the passenger. At an end of auxiliary seatbelt, a secondary anchor (80) is mounted on the vehicle body (B) or passenger seat (D) at the opposite side from the first anchor (70).
FIGS. 2 and 3 disclose a conventional anchor being used for a seatbelt. The conventional anchor made of a steel plate (S) comprises a lower part (1a) and upper part (1b). A slot (2) is provided at the mid of lower part (1a) for suspending a seatbelt. A bolt hole (5) is formed at the center of upper part (1b). The belts (20, 40) are installed through the slot (2). A bolt (6) is installed through the bolt hole (5) of anchor. The anchor is mounted on the vehicle body (B) by means of bolt (6) and busing (7).
FIGS. 4 and 5 disclose a conventional pillar anchor as another example. Except the lower part, the conventional pillar anchor has a similar structure to that of conventional anchor as shown in FIGS. 2 and 3. This type anchor also applies the means of bolt (6) and busing (7) when the pillar anchor is mounted on the vehicle body (B).
As shown in FIGS. 2 to 5, the upper part (1b) of convention anchor must be apart a certain distance from a vehicle body (B) for properly operating the seatbelt. To do so, the conventional anchor adopts a bushing (7) to apart the upper part (1b) of anchor from the vehicle body (B). The conventional pillar anchor is also applying a bushing (7) during the assembly to maintain a certain clearance between the upper part (1b) of anchor and vehicle body (B). Then, the conventional anchors could be mounted on the vehicle body by means of a bolt (6).
Depending on the vehicle types, one or more bushings (7) are installed to adjust the clearance. Accordingly, the bolt (6) length would be varied depending on the number of installed bushings. When the number of installed bushings between the conventional anchor and vehicle body is increased, the mounted bolt must be lengthened. Thus, the bolt price would be increased.
Even worse, many assembly workers frequently forget to install the bushings (7) to provide a proper clearance during the assembly. Therefore, the seatbelt will be jammed easily during the operation. The malfunction of seatbelt operation would be a cause of potential danger.
The present invention has improved by considering and solving the problems of conventional anchors. The object of the present invention is to provide an anchor with an improved upper structure for providing a proper clearance between the upper part of anchor and vehicle body without adapting a bushing.
To achieve the above object, a new concept of mini anchor with an improved upper structure has developed. The mini anchor comprises a lower part having a slot for suspending the seatbelt and an upper part having a bolt-mounting sink. The upper part of mini anchor is formed a cylindrical basin with a predetermined depth.
According to the present invention, a process for manufacturing the mini anchor with an improved upper part is described as follows:
The manufacturing process comprises a first step, stamping process to form an initial conical shape (S3a) having a predetermined depth; a second step, pressing process is to round up a tip of initial conical shape (S3a) for forming a transition conical shape (S3b). A basin (S4a) of transition conical shape (S3b) has less depth than that of previous step; a third step, expanding process is to form a transition semi-spherical shape (S3c) by expanding radial direction. A basin (S4b) of transition semi-spherical shape (S3c) has less depth than that of previous step; a fourth step, pressing process is to form a cylindrical basin (S3d) having a final depth with flat bottom (S4c); and final step, punching process is to form a bolt hole (5) at the bottom center of cylindrical basin (S4c).
There are four alternative processes for manufacturing the mini anchor with an improved upper structure disclosed in this specification. The basic process of four alternative processes for manufacturing the mini anchor is similar to the process mentioned above.
One of four alternative processes for manufacturing the mini anchor illustrates that a first step, stamping process for forming an initial conical shape (S3a) is same as the process mentioned before except a piercing process (S6). A tip of initial conical shape (S3a) is simultaneously pierced while the steel plate (S) is forming the initial conical shape (S3a).
Since the rest of process are identical with the previous process mentioned above, the detailed descriptions are omitted here.
Another alternative process for manufacturing the mini anchor illustrates that second step of pressing process for forming a transition conical shape (S3b) is same as previous process mentioned above except a piercing process (S6). A tip of transition conical shape (S3b) is simultaneously pierced while the steel plate (S) is forming a transition conical shape (S3b).
Because the first and third to final steps are identical with the previous process mentioned above, the detailed descriptions are skipped here.
Still other process for manufacturing the mini anchor with an improved upper part is described that a first step, stamping process is to form an initial trapezoidal shape (S13a) having a predetermined depth. Second step, pressing process is to form a transition trapezoidal shape (S13b) by expanding the initial transition trapezoidal shape (S13a) to the radial direction. Third step, expanding process is to form a secondary transition trapezoidal shape (S13c) by expanding wider than that of previous step. Forth step, pressing process is to form a cylindrical basin shape (S13d) having a final depth with flat bottom surface. Final step, punching process is to punch out a bolt-hole (S5) for installing a bolt.